The whole point of Nooku is to help you get things done, quickly. The tutorials are in development and are designed to help you do just that. You should have already been through the Get Started section and be ready to go.
If you are developing Joomla extension we recommend heading over to the Joomlatools Developer Portal and review and make use of the "Tools" listed there. The combination can really help streamline your development set up for different projects.
If you have a great Tutorial idea, then Get Writing!